This invention relates to an arrangement for an injection pump in an internal combustion engine.
A large diesel engine refers in this connection to such an engine that may be employed, for example, as the main propulsion engine or the auxiliary engine for a ship or for a power plant for producing electricity and/or heat energy.
In order to control the operation of a fuel injection pump and to provide exact timing for the injection a control valve controlled by a solenoid is with advantage used. Especially in case the fuel to be utilized is heavy fuel, which may cause clogging problems, a spill valve may be utilized as a control valve, the operation of which is controlled by means of a separate pressure medium circuit provided with a solenoid valve so that pressure medium, for instance oil, is continuously fed into the control valve and onward into a spill passage. The injection of fuel is started by closing the solenoid valve, whereby the pressure medium remains in the feed duct between the solenoid valve, a non-return valve and the control valve and provides, due to suitable dimensions of the feed duct, a pressure wave effect closing the control valve. The principles of operation of a system of this kind are described for instance in the publication GB 2279706, which is hereby incorporated by reference for this part.